I got my PhD from University of Illinois under Professor Klara Nahrstedt in the MONET group. While in Illinois, I worked on the DSRT project and the GRACE project. In particular, I developed DSRT-NT, GRACE-1, and GRACE-OS. My research interests are in the areas of operating systems, networks, multimedia, and real-time systems, with an emphasis on the design of energy-efficient and QoS-aware operating systems.

I got my B.S. and M.S. from Peking University, China, in 1996 and 1999, respectively. During my master study, I worked with Professors Fuqing Yang and Hong Mei in the areas of program analysis and component-based software reuse.

Software Design Engineer, Microsoft, 04/2006-present
Working on embedded Windows operating systems.

Research Engineer, DoCoMo USA Labs, 07/2004-03/2006
Researched and designed operating systems for next-generation cellphones, with an emphasis on energy efficiency and reliability of device drivers.

Research Assistant, University of Illinois at Urbana-Champaign, 08/2000-07/2004
Developed DSRT-NT, Dynamic Soft Real-Time CPU scheduler for Windows and GRACE-1, the first version of the Illinois GRACE cross-layer adaptive system for energy. Designed, implemented, and evaluated GRACE-OS, an energy-efficient and QoS-aware operating system for mobile multimedia devices.

Intern, Multimedia Management Group, Microsoft Research Asia, 05/2001-08/2001
Studied and compared two protocols, SOAP and ICAP, for content service networks.

Intern, Programmer Productivity Research Center, Microsoft Research, 05/2000-08/2000
Developed a generic framework to test the parameters and return value of APIs.

Research Assistant, Peking University, 09/1995-07/1999
Led a five-member team to develop JBPAS, a program-understanding system. Participated into the development of JBCL, a database library system supporting component-based software engineering.

1. NEMOS (NExt Mobile Operating System)
NEMOS targets to next generation mobile devices, in particular, smartphones. I am working in two areas of NEMOS, one in energy saving and one in device driver management for simple programming, portability, and reliability.

2. GRACE-OS
The core part of the Illinois GRACE cross-layer adaptive system. GRACE-OS uses a hierarchical approach to coordinate the adaptation of CPU frequency and voltage, operating system scheduling, and applications to maximize multimedia quality and minimize CPU energy. GRACE-OS has been implemented as an extension to the Linux kernel 2.4 and 2.6.

3. DSRT
Dynamic Soft Real-Time CPU scheduler for QoS provisioning. DSRT allows applications to profile CPU demands and reserve CPU accordingly. It then schedules admitted applications with soft performance guarantees. DSRT has been implemented as a middleware on Windows, Unix, and Linux as well as an extension to the Linux kernel. DSRT is available at http://cairo.cs.uiuc.edu/software/DSRT-2/dsrt-2.html. DSRT has been widely downloaded and is deployed in the Globus Toolkit In Argonne National Laboratory and the Gaia Project in University of Illinois.

4. JBPAS
A program understanding system for C++ and Smalltalk. JBPAS parses source code to extract program information and presents abstract program views such as design document in Rational Rose format. JBPAS has been developed as a product at Peking University.

5. JBCL
A database library system that supports the classification, indexing, storage, retrieval, and composition of software components such as classes and design documentation. JBCL consists of backend of SQL server in Windows and Informix in Solaris as well as web-interface.

Papers in refereed journals and magazines

1. W. Yuan and K. Nahrsted, Energy-Efficient CPU Scheduling for Multimedia Applications, ACM Transaction on Computer Systems, 24(3): 292-331, August 2006.
2. W. Yuan, K. Nahrstedt, S. Adve, D. Jones, and R. Kravets, GRACE-1: Cross-Layer Adaptation for Multimedia Quality and Battery Energy, IEEE Transaction on Mobile Computing, 5(7): 799-815, July 2006.
3. W. Yuan and K. Nahrstedt, Energy-Efficient Soft Real-Time CPU Scheduling for Mobile Multimedia Systems, Operating Systems Review, 37(5): 149-163, December 2003.
4. D. Sachs, W. Yuan, C. Hughes, A. Harris, S. Adve, D. Jones, R. Kravets, and K. Nahrstedt, GRACE: A Cross-Layer Adaptation Framework for Saving Energy, IEEE Computer, 36(12): 50-51, Dec 2003.
5. X. Gu, K. Nahrstedt, W. Yuan, D. Wichadakul, and D. Xu, An XML-based Quality of Service Enabling Language for the Web, Journal of Visual Language and Computing, 13(1):61-95, Feb 2002.

   Papers in refereed conferences

6. J. Sun, W. Yuan, M. Kallahalla, and N. Islam, HAIL: A Language for Easy and correct Device Access, Proc. of ACM Conference on Embedded Software, jersey City, NJ, Sep 2005, pp.1-9.
7. W. Yuan and K. Nahrstedt, Practical Voltage Scaling for Mobile Multimedia Devices, Proc. of ACM Multimedia 2004, New York, NY, Oct 2004.
8. W. Yuan and K. Nahrstedt, Energy-Efficient Soft Real-Time CPU Scheduling for Mobile Multimedia Systems, Proc. of 19th ACM Symposium on Operating Systems Principles (SOSP'03), Bolton Landing, NY, Oct 2003.
9. W. Yuan and K. Nahrstedt, Process Group Management in Cross-Layer Adaptation, Proc. of SPIE/ACM Multimedia Computing and Networking Conference (MMCN'04), Santa Clara, CA, January 2004.
10. W. Yuan and K. Nahrstedt, Buffering Approach for Energy Saving in Video Sensors, Proc. of IEEE International Conference on Multimedia and Expo (ICME'03), Baltimore, MD, July 2003, 289-292.
11. C. Ong, K. Nahrstedt, and W. Yuan Quality of Protection For Mobile Multimedia Applications, Proc. of IEEE International Conference on Multimedia and Expo (ICME'03), Baltimore, MD, July 2003, 137-140.
12. W. Yuan and K. Nahrstedt, ReCalendar: Calendaring and Scheduling Applications with CPU and Energy Resource Guarantees for Mobile Devices, Proc. of IEEE International Conference on Pervasive Computing and Communication (PerCom'03), Dallas-Fort Worth, TX, March 2003, 425-432.
13. W. Yuan, K. Nahrstedt, S. Adve, D. Jones, and R. Kravets, Design and Evaluation of A Cross-Layer Adaptation Framework for Mobile Multimedia Systems, Proc. of SPIE/ACM Multimedia Computing and Networking Conference (MMCN'03), Santa Clara, CA, January 2003, 1-13.
14. W. Yuan and K. Nahrstedt, A Middleware Framework Coordinating Processor/Power Resource Management for Multimedia Applications, Proc. of IEEE Globecom 2001, San Antonio, Texas, November 2001, 1984-1988.
15. W. Yuan, K. Nahrstedt, and K. Kim, R-EDF: A Reservation-Based EDF Scheduling Algorithm for Multiple Multimedia Task Classes, Proc. of the 7th IEEE Real-Time Technology and Applications Symposium (RTAS'01), Taiwan, May 2001, 149-154.

    Papers in refereed workshops

16. W. Yuan and K. Nahrstedt, Integration of Dynamic Voltage Scaling and Soft Real-Time Scheduling for Open Mobile Systems, Proc. of the 12th International Workshop on Network and Operating Systems Support for Digital Audio and Video (NOSSDAV'02), Miami Beach, FL, May 2002, 105-114.
17. S. Adve, A. Harris, C. Hughes, D. Jones, R. Kravets, K. Nahrstedt, D. Sachs, R. Sasanka, J. Srinivasan, and W. Yuan, The Illinois GRACE Project: Global Resource Adaptation through CoopEration, Proc. of Workshop on Self-Healing, Adaptive and self-MANaged Systems (SHAMAN02), New York City, NY, June, 2002.
18. W. Yuan, K. Nahrstedt, and X. Gu, Coordinating Energy-Aware Adaptation of Multimedia Applications and Hardware Resource, Proc. of the 9th ACM Multimedia (Multimedia Middleware Workshop), Ottawa, Canada, October 2001, 60-63.

    Papers published during M.S. study in Peking University, China

19. H. Mei, T. Xie, W. Yuan, and F. Yang, Component Metrics in Jade Bird Component Library System, Chinese Journal of Software, 11(5): 634-641, May 2000.
20. T. Xie, W. Yuan, H. Mei, and F. Yang, JBOOMT: Jade Bird Object-Oriented Metrics Tool, Chinese Journal of Electronics (English version), 9(2): 202-207, April 2000.
21. H. Mei, Q. Wu, W. Yuan, and F. Yang, A Smalltalk Program Understanding System BDCom-ST, Chinese Journal of Computers, 23(8):882-886, 2000.
22. F. Yang, H. Mei, K. Li, W. Yuan, and Q. Wu, Jade Bird III: A System Supporting Component Reuse, Chinese Computer Science, 26(5): 50-55, May 1999.
23. W. Yuan, T. Xie, and X. Chen, Introduction to Object-Oriented Metrics, Chinese Computer Science, 26(5):65-70, May 1999.
24. Y. Guo, W. Yuan, X. Chen, X. Zhou, Software Reengineering: Concepts and Frameworks, Chinese Computer Science, 26(5), May 1999.
25. W. Yuan, X. Chen, T. Xie, and Y. Guo, The Research and Development of Reverse Engineering, Chinese Computer Science, 26(5):71-77, May 1999.
26. B. Huang, B. Qian, W. Yuan, H. Mei, and F. Yang, An Automatic Approach to Recovering OOD Models from C++ Programs, Chinese Journal of Advanced Software Research, 2(6):106-113, 1999.
27. W. Yuan, X. Chen, T. Xie, H. Mei, and F. Yang, C++ Program Information Database for Analysis Tools, Proc. of 27th Conference on Technology of Object-Oriented Languages and Systems (TOOLS98), Beijing, China, September 1998, 173-180.
28. F. Yang, H. Mei, W. Yuan, Q. Wu, Experiences writing C++ Compiler Front End, ACM SIGPLAN Notices, 33(9):95-102, 1998.
29. H. Mei, W. Yuan, Q. Wu, and F. Yang, BDCom-C++: A C++ Program Understanding System, Chinese Journal of Electronics (English Version), 6(2): 64-69, April 1997.

    Thesis

30. Wanghong Yuan, GRACE-OS: An Energy-Efficient Mobile Multimedia Operating System, Ph.D. Thesis, Department of Computer Science, University of Illinois at Urbana-Champaign, October, 2004.
31. Wanghong Yuan, JBPAS: An Object Oriented Program Understanding System, M.S. Thesis, Department of Computer Science, Peking University, July, 1999.

1. TPC Member, IEEE International Symposium on Wearable Computers (ISWC 2006), Montreux, Switzerland.
2. TPC Member, Multimedia Computing and Networking (MMCN 2006), San Jose, CA.
3. TPC Member, ACM Multimedia 2005 (short papers), Singapore.
4. TPC Member, First Workshop on System and Networking for Smart Objects (SaNSO05), Fukuoka, Japan.
5. Reviewer for journals: ACM Transaction on Computer Systems, ACM Transaction on Embedded Computing Systems, IEEE Transactions on Mobile Computing, IEEE Transaction on Parallel and Distributed Systems, IEEE Transactions on Computers, ACM Multimedia System Journal, Computer Networks Journal and IEEE Wireless Communication.